How do exposed layers of sedimentary rock in the Grand Canyon reveal clues about the geologic time scale?
a. The chemical composition of each layer indicates the conditions on Earth when the layer was deposited.
b. Fossils of soft-bodied animals are prevalent in sedimentary rock.
c. Radiometric dating using 14C of fossils in each layer can accurately predict their age up one million years ago.
d. The chemical composition of each layer can be determined by radiometric dating.
e. The oldest fossils are found near the surface, while the most recent fossils are found at deeper layers.
ANSWER: a
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_____ blunt AluI ends from Xenopus laevis. _____ sticky NotI ends from Xenopus laevis. _____ blunt AluI ends from bacteria. _____ sticky NotI ends from bacteria. _____ sticky EcoRI ends from Xenopus laevis. _____ sticky EcoRI ends from bacteria.
________ can be detected through a blood test that detects a specific antigen called PSA
Fill in the blank(s) with correct word
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A) neurotransmitter molecules are stored in the synaptic cleft. B) action potentials trigger chemical changes that make the synaptic vesicles fuse with each other. C) vesicles containing neurotransmitters diffuse to the receiving cell's plasma membrane. D) neurotransmitter molecules bind to receptors in the receiving cell's plasma membrane.
Gram-negative bacilli are often treated with
A. aminoglycosides. B. vancomycin. C. synercid. D. isoniazid. E. penicillin G.